
import java.util.Scanner;

/**
 * Created with IDEA
 * author:ju bai
 * Date:2021/4/12
 * Time:16:41
 **/
public class Main2 {

    public static void main (String[] args){
        Scanner sc = new Scanner(System.in);
        while(sc.hasNext()){
            String str1 = sc.nextLine();
            String str2 = sc.nextLine();
            func(str1,str2);
        }
    }

    /**
     * 每日一题-删除公共字符
     * 100%
     * @param str1
     * @param str2
     */
    public static void func(String str1,String str2){
        char[] array = str1.toCharArray();//将str1放进字符串数组中
        for(int i = 0;i<array.length;i++){
            String ch = array[i]+"";
            if(!str2.contains(ch)){//str2若与其不相等，输出
                System.out.print(ch);
            }
        }
    }
}
